A semiconductor device such as a semiconductor memory, or the like, may have a fuse in a metal wiring layer. The fuse can be configured to be cut by irradiating laser light or applying a current of a threshold value or higher. The characteristics of an electronic circuit assembled in a semiconductor device may be adjusted (trimmed) or a defective portion within the semiconductor device may be separated by selectively cutting the fuse. In general, a fuse is provided in a metal wiring layer and made of the same material as that of a metal wiring.
Aluminum (Al) has been widely used as a wiring material, and recently, wiring resistance is required to be reduced, particularly in a power semiconductor device which consumes a great amount of power. Thus, a structure of a semiconductor device using copper (Cu) having higher conductivity than that of Al, as a wiring material, has been proposed. That is, a fuse made of copper may be formed in the copper wiring layer.
However, when the fuse is cut by laser light or the like, fragments of copper constituting the fuse scatter within the wiring structure. Copper is easily spread within silicon oxide, which is a material commonly used in an interlayer insulating layer, so it may reach an element region formed on the semiconductor substrate and may likely negatively affect an element operation. Further, a fuse made of copper can easily corrode at a surface that is exposed when the fuse is cut. This corrosion may reach the vicinity of the semiconductor substrate through a current path connected to the fuse.